How River Phoenix KNEW he was suffering an overdose the night he died: Friend reveals the actor's harrowing last few minutes before he collapsed at Johnny Depp's LA nightclub almost 20 years ago

Tragic: River Phoenix pictured here in 1991 was tipped for mega-stardom before his death two years later from a drugs overdose in LA

River Phoenix knew he was experiencing an overdose from a deadly cocktail of cocaine and heroin the night of his death at Johnny Depp's Los Angeles nightclub claims a friend of the actor who was there that fateful evening.

As the world prepares to mark 20-years since the death of Phoenix at the tragically young age of 23, his friend and former Helonious Monster front-man Bob Forrest has revealed the harrowing last moments before the actor collapsed.

Unsteady on his feet and ghostly white, Forrest recalls how Phoenix turned to him on Halloween, 1993 and pleaded, 'I don't feel so good. I think I'm OD'ing' before he returned to the crowd to hear Depp's band play to only fall into a fit minutes later.

Describing Phoenix, the critically acclaimed star of Indiana Jones And The Last Crusade and Stand By Me, as a frustrated rock star, Forrest said that in the days leading up to his death he had fallen in with Red Hot Chili Peppers’ guitarist John Frusciante.

The two would take large amounts of drugs together, embarking on huge binges.

'River stayed with John for the next few days, and probably didn’t get a minute of sleep,' Forrest writes in his forthcoming book Running With Monsters according to The New York Post.

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Hollywood, Los Angeles, California: 1993 - Tributes to River Phoenix outside The Viper Room - the club owned by Johnny Depp where the 23-year-old actor died on October 31st

'The drug routine stayed pretty consistent for all of us. First, smoke crack or shoot coke directly into a vein for that ninety-second, electric brain-bell jangle.

'Then shoot heroin to get a grip and come down enough to be able to carry on a conversation for a few minutes before you start the cycle again.'